BIODEGRADABLE TRIBLOCK COPOLYMERS AND PROCESS FOR THEIR PREPARATION

• US 20020161134A1
• Filed: 02/07/2001
• Published: 10/31/2002
• Est. Priority Date: 02/14/2000
• Status: Active Grant

• Current Assignee: Korea Advanced Institute of Science and Technology
• Original Assignee: Korea Advanced Institute of Science and Technology
• Inventors: Kim, Soo Hyun, Lee, Soo-Hong, Kim, Young Ha, Park, Ki Dong
• Granted Patent: US 6,476,156 B1
• Time in Patent Office: Days
• US Class Current: 525/408
• CPC Class Codes: C08G 63/664 derived from hydroxy carboxylic acids
• CPC Class Codes: C08G 65/3324 cyclic
• CPC Class Codes: C08L 2666/18 Polyesters or polycarbonates according to C08L67/00 - C08L69/00; Derivatives thereof
• CPC Class Codes: C08L 71/02 Polyalkylene oxides

Abstract

The present invention relates to polyethyleneglycol/polylactide (or polyglycolide or polycaprolactone)/polyethyleneglycol triblock copolymers with an enhanced reactivity, and process for their preparation.

More specifically, the present invention is directed to triblock copolymers that are obtained by the process comprising the step of synthesizing a polylactide (or polyglycolide or polycaprolactone) having hydroxy groups at both ends and the step of coupling said polylactide with polyethyleneglycol having an acylhalide group of a high reactivity at one of its ends, and the process for preparing the same.

Since the triblock copolymer according to the present invention has an ester structure with good biocompatibility, it can be applied extensively for biomaterials used in tissue engineering, in a matrix that slowly releases drugs, etc.

Claims

1. A biodegradable triblock copolymer selected from the group consisting of copolymers of formula (1) to (4).

<

formula 1>

PEG-COO-PL-OCO-PEG

<

formula 2>

PEG-COO-PG-OCO-PEG

<

formula 3>

PEG-COO-(PLPG)-OCO-PEG <

formula 4>

PEG-COO-PCL-OCO-PEG

In the formula,

PEG is polyethyleneglycol,

PL is polylactide,

PG is polyglycolide,

PCL is polycaprolactone.

2. The biodegradable triblock copolymer according to claim 1, wherein a molecular weight of PEG is 750 to 10,000.

3. The biodegradable triblock copolymer according to claim 1, wherein a molecular weight of polylactide, polyglycolide, polylactide/polyglycolide or polycaprolactone is 500 to 30,000.

4. A method for preparing a triblock copolymer which comprises coupling polyethyleneglycol having an acylhalide group of a high reactivity at one of its ends with polylactide, polyglycolide, polylactide/polyglycolide or polycaprolactone having a hydroxy group at both ends in the presence of pyridine.